docs: def get_user(self, user_id=None):
          """
          Returns a user for the specified user as user.
  
          GET users/:id/
  
          :param int user_id: (optional) The id assigned to a user
  
          """
          if user_id:
              return self.get('/users/{0}/'.format(user_id))
          return self.get('/users/me/')